Literally it reads:
Boyko, Boycho, Boyka - a "wishful name" - may others be afraid of him, may he be good in battle.
Clarification - Boycho is a variant of Boyko, Boyka is the female version.
Clarification number 2 - the possible roots of the name (not listed, but obvious to Bulgarians) are either the verb boya se - to be afraid of, or the noun boy - battle or beating up. [And those two are, in fact, etymologically connected].